1. Field of the Invention
The present invention is a self locking door lock.
2. Description of Related Art
It is usually desirable to provide some type of safety device on a door to prevent unwanted intruders from entering the structure. One common type of safety device is the dead bolt lock. Although effective in securing the door, the occupant of the structure is unable to view a visitor unless they unlock the device and open the door. To compensate for this deficiency some doors contain a peep hole which allows the occupant to view the person on the other side of the door. Alternatively, some structures are equipped with a chain which allows the door to be opened a predetermined distance so that the occupant can view the visitor. Conventional chain locks are relatively weak and can be broken by an intruder with a swift kick to the door. It is therefore desirable to have a door check which can withstand an excessive force applied to the door.
U.S. Pat. No. 540,019 issued to Gay and U.S. Pat. No. 222,338 issued to Wittich disclose door checks that cooperate with a dead bolt lock to secure the door in a slightly opened position. The door checks include a latch that is constructed from a solid metal plate or bar which increases the strength of the assembly. The latches are typically mounted to the structure with wood screws attached to a mounting bracket. It has been found that an intruder can separate the screws from the wall by applying a large force to the door. It would therefore be desirable to provide a door lock that is strong enough to withstand any bodily force and would allow the occupant to slightly open the door while in the locked position.